Official GST return manuals for routine filing, nil returns, composition returns, and annual return workflows.
GSTR-1 filing manual
GSTN
Official GSTN guide for preparing and filing Form GSTR-1.
GSTR-3B filing manual
GSTN
Official GSTN guide for monthly Form GSTR-3B filing.
GSTR-4 annual return manual
GSTN
Official GSTN guide for annual return filing in Form GSTR-4.